Gale & Snowden Architects
Notes from Passive Office Study Tour, Portugal
1.0 Introduction The following details the findings and observations from the Gale & Snowden Passive Office visit in Lisbon Portugal of the Solar XXI building.
2.0 Details of the Passive Office Building name: Solar XXI and is the National Laboratory of Energy and Geology (LNEG) Completed:
2006
Floor area:
Total: 1500 m2, useful 1000 m2
Building type:
Offices and Laboratory
No of Floors:
4 including a basement
2.1 Key features The building has been designed with the following key features: Natural ventilation – with cross flow, stack and single sided ventilation with high and low level openings – all manually controlled. Glazed louvres above doors enabled air to move from the office space into the stack corridor. Central full height corridor throughout the building with high level stack openings Stairwells at either end of the building on the east and west side, both of which have high level stack openings Thermal mass in solid floor and internal walls. Walls consisted of an external wall insulation system. Innovative use of mass in the floor with a channel for floor services. South facing orientation – maximising solar gain in winter with large south facing double glazed units Integrated vertical PV system on the south facing façade with innovative heat recovery from behind the PV panels to the office space via high and low level openings. Additional pitched PV system in the adjacent car park area. Solar hot water panels on the roof for pre-heating a thermal store for heating only. The building has no hot water supplies. The design featured 32 x 300mm diameter concrete earth tube system ranging from 5-15 metres in length at a depth of 4-5 m in the ground. During elevated internal temperatures the fans were switched on to pull air through the ground to help cool the space.
2.2 Thermal Details Windows:
Double glazed units with a Uvalue of 2.6 W/m2/K. External shading to control solar gain in summer.
Walls:
220mm masonry brick internal, 60mm EPS insulation external – Uvalue 0.26 W/m2/K
Floors:
Concrete and screed on top of 100mm EPS insulation – Uvalue unclear
Roof:
Concrete with 100mm EPS on top - Uvalue unclear
Air Permeability: Untested due to warm winter conditions and Portuguese building regulations
April 2012
Page 3 of 9